On 2016-07-22 11:11, Marc Zyngier wrote: > On 22/07/16 18:56, Stefan Agner wrote: >> On 2016-07-22 10:49, Marc Zyngier wrote: >>> On 22/07/16 18:38, Andrew Jones wrote: >>>> On Fri, Jul 22, 2016 at 04:40:15PM +0100, Marc Zyngier wrote: >>>>> On 22/07/16 15:35, Andrew Jones wrote: >>>>>> On Fri, Jul 22, 2016 at 11:42:02AM +0100, Andre Przywara wrote: >>>>>>> Hi Stefan, >>>>>>> >>>>>>> On 22/07/16 06:57, Stefan Agner wrote: >>>>>>>> Hi, >>>>>>>> >>>>>>>> I tried KVM on a Cortex-A7 platform (i.MX 7Dual SoC) and encountered >>>>>>>> this stack trace immediately after invoking qemu-system-arm: >>>>>>>> >>>>>>>> Unable to handle kernel paging request at virtual address ffffffe4 >>>>>>>> pgd = 8ca52740 >>>>>>>> [ffffffe4] *pgd=80000080007003, *pmd=8ff7e003, *pte=00000000 >>>>>>>> Internal error: Oops: 207 [#1] SMP ARM >>>>>>>> Modules linked in: >>>>>>>> CPU: 0 PID: 329 Comm: qemu-system-arm Tainted: G W >>>>>>>> 4.7.0-rc7-00094-gea3ed2c #109 >>>>>>>> Hardware name: Freescale i.MX7 Dual (Device Tree) >>>>>>>> task: 8ca3ee40 ti: 8d2b0000 task.ti: 8d2b0000 >>>>>>>> PC is at do_raw_spin_lock+0x8/0x1dc >>>>>>>> LR is at kvm_vgic_flush_hwstate+0x8c/0x224 >>>>>>>> pc : [<8027c87c>] lr : [<802172d4>] psr: 60070013 >>>>>>>> sp : 8d2b1e38 ip : 8d2b0000 fp : 00000001 >>>>>>>> r10: 8d2b0000 r9 : 00010000 r8 : 8d2b8e54 >>>>>>>> fec 30be0000.ethernet eth0: MDIO read timeout >>>>>>>> r7 : 8d2b8000 r6 : 8d2b8e74 r5 : 00000000 r4 : ffffffe0 >>>>>>>> r3 : 00004ead r2 : 00000000 r1 : 00000000 r0 : ffffffe0 >>>>>>>> Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user >>>>>>>> Control: 30c5387d Table: 8ca52740 DAC: fffffffd >>>>>>>> Process qemu-system-arm (pid: 329, stack limit = 0x8d2b0210) >>>>>>>> Stack: (0x8d2b1e38 to 0x8d2b2000) >>>>>>>> 1e20: ffffffe0 >>>>>>>> 00000000 >>>>>>>> 1e40: 8d2b8e74 8d2b8000 8d2b8e54 00010000 8d2b0000 802172d4 8d2b8000 >>>>>>>> 810074f8 >>>>>>>> 1e60: 81007508 8ca5f800 8d284000 00010000 8d2b0000 8020fbd4 8ce9a000 >>>>>>>> 8ca5f800 >>>>>>>> 1e80: 00000000 00010000 00000000 00ff0000 8d284000 00000000 00000000 >>>>>>>> 7ffbfeff >>>>>>>> 1ea0: fffffffe 00000000 8d28b780 00000000 755fec6c 00000000 00000000 >>>>>>>> ffffe000 >>>>>>>> 1ec0: 8d2b8000 00000000 8d28b780 00000000 755fec6c 8020af90 00000000 >>>>>>>> 8023f248 >>>>>>>> 1ee0: 0000000a 755fe98c 8d2b1f08 00000008 8021aa84 ffffe000 00000000 >>>>>>>> 00000000 >>>>>>>> 1f00: 8a00d860 8d28b780 80334f94 00000000 8d2b0000 80334748 00000000 >>>>>>>> 00000000 >>>>>>>> 1f20: 00000000 8d28b780 00004000 00000009 8d28b500 00000024 8104ebee >>>>>>>> 80bc2ec4 >>>>>>>> 1f40: 80bafa24 8034138c 00000000 00000000 80341248 00000000 755fec6c >>>>>>>> 007c1e70 >>>>>>>> 1f60: 00000009 00004258 0000ae80 8d28b781 00000009 8d28b780 0000ae80 >>>>>>>> 00000000 >>>>>>>> 1f80: 8d2b0000 00000000 755fec6c 80334f94 007c1e70 322a7400 00004258 >>>>>>>> 00000036 >>>>>>>> 1fa0: 8021aa84 8021a900 007c1e70 322a7400 00000009 0000ae80 00000000 >>>>>>>> 755feac0 >>>>>>>> 1fc0: 007c1e70 322a7400 00004258 00000036 7e9aff58 01151da4 76f8b4c0 >>>>>>>> 755fec6c >>>>>>>> 1fe0: 0038192c 755fea9c 00048ae7 7697d66c 60070010 00000009 00000000 >>>>>>>> 00000000 >>>>>>>> [<8027c87c>] (do_raw_spin_lock) from [<802172d4>] >>>>>>>> (kvm_vgic_flush_hwstate+0x8c/0x224) >>>>>>>> [<802172d4>] (kvm_vgic_flush_hwstate) from [<8020fbd4>] >>>>>>>> (kvm_arch_vcpu_ioctl_run+0x110/0x478) >>>>>>>> [<8020fbd4>] (kvm_arch_vcpu_ioctl_run) from [<8020af90>] >>>>>>>> (kvm_vcpu_ioctl+0x2e0/0x6d4) >>>>>>>> [<8020af90>] (kvm_vcpu_ioctl) from [<80334748>] >>>>>>>> (do_vfs_ioctl+0xa0/0x8b8) >>>>>>>> [<80334748>] (do_vfs_ioctl) from [<80334f94>] (SyS_ioctl+0x34/0x5c) >>>>>>>> [<80334f94>] (SyS_ioctl) from [<8021a900>] (ret_fast_syscall+0x0/0x1c) >>>>>>>> Code: e49de004 ea09ea24 e92d47f0 e3043ead (e5902004) >>>>>>>> ---[ end trace cb88537fdc8fa206 ]--- >>>>>>>> >>>>>>>> I use CONFIG_KVM_NEW_VGIC=y. This happens to me with a rather minimal >>>>>>>> qemu invocation (qemu-system-arm -enable-kvm -M virt -cpu host >>>>>>>> -nographic -serial stdio -kernel zImage). >>>>>>>> >>>>>>>> Using a bit older Qemu version 2.4.0. >>>>>>> >>>>>>> I just tried with a self compiled QEMU 2.4.0 and the Ubuntu 14.04 >>>>>>> provided 2.0.0, it worked fine with Linus' current HEAD as a host kernel >>>>>>> on a Midway (Cortex-A15). >>>>>> >>>>>> I can reproduce the issue with a latest QEMU build on AMD Seattle >>>>>> (I haven't tried anywhere else yet) >>>>>> >>>>>>> >>>>>>> Can you try to disable the new VGIC, just to see if that's a regression? >>>>>> >>>>>> Disabling NEW_VGIC "fixes" guest boots. >>>>>> >>>>>> I'm not using defconfig for my host kernel. I'll do a couple more >>>>>> tests and provide a comparison of my config vs. a defconfig in >>>>>> a few minutes. >>>>> >>>>> Damn. It is not failing for me, so it has to be a kernel config thing... >>>>> If you can narrow it down to the difference with defconfig, that'd be >>>>> tremendously helpful. >>>> >>>> It's PAGE_SIZE; 64K doesn't work, 4K does, regardless of VA_BITS >>>> selection. >>> >>> That definitely doesn't match Stefan's report (32bit only has 4k). I'll >> >> Hehe, was just plowing through code and came to that conclusion, glad I >> got that right :-) >> >> What defconfig do you use? I could reproduce the issue also with >> multi_v7_defconfig + ARM_LPAE + KVM. > > I have my own config file with the crap I need to make things work on > the various platforms I have around. If multi_v7_defconfig works on the > cubietruck, I'll give it a spin tomorrow. I need a beer now. > >> Btw, I am not exactly on vanilla 4.7-rc7, I merged Shawns for-next + >> clock next to get to the bits and pieces required for my board... >> >> That said, it works fine otherwise, and the stacktrace looks rather >> platform independent... > > Yeah, and that's the worrying part. FWIW, I tried here with Qemu 2.6.0, same stack trace... -- Stefan _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm